Engine mounting



Oct. 27, 1931. c. E. SUMMERS ET AL ENGINE MOUNT ING Filed Dec. 26, 1925 2 Sheets-Sheet l gwue'nl' 01,; (f 3127777225 X fime 1931. c. E. SUMMERS ET AL 1,829,723

ENGINE MOUNTING Filed Dec. 26, 1925 2 Sheets-Sheet. 2

attoz wag .of the vibrations of the en 'ne Patented Oct. 21,1931

UNITE-ID STATES- PATENT OFFICE CALEB E. sumas m noel-in. xmmnrn mm, or nm'norr, mcnzem, assrenons ro GENERAL morons imsmncn comma-roar, or mmzorr, MICHIGAN, a consona- TION OF DELAWARE moms uotmrme' Application filed December, 1085. Serial 10. 77,885.

The invention relates to means for supporting bodies which are subject to vibratory or oscillatorymovements and for preventing transmission of such movements to the base whereby the body is sustained or suspended. It finds especial utility in connection with motors or machines in which a tendenc to vibratory movements is produced by un alanced inertia forces due to the actuation of unbalanced moving parts.

Although obviously of more generic application, the invention will be herein scribed as applied to an internal combustion engine of the four cylinder type. In this embodiment of the invention it will have as its function the prevention of transmission to the frameor bed of the. engine, for example, to the frame of an automobile inwhich the engine constitutes thesource of owier, y Y ue chiefly'to unbalanced inertia orces resulting from the piston and connecting rod motions.

It is well known that an engine of the type mentioned is not inherently balanced as to its piston movements, and as a result, when unrestrained, the entire engine moves slightly in a direction parallel to the cylinder celrter lines at twice crankshaft frequency. It

is also well-known that the cylinder block tends to swa lightly from side side at double cra ha frequency, this being known as piston inertia torque, and may be expaiined as follows:

en the crank throwsare in a vertical position, all pistons are at a standstill so they have no kinetic energy. Ninety degrees later,

all four pistons are moving at a high velocity. This energy is drawn from and returned to the flywheel twice each revolution of the crankshaft. Since the ener of the system is constant, the flywheel is a ternately accelerated and decelerated, such force having a'reaction on the cylinder-block in the form of piston side ressures which tend to sway the block bac and forth through a definite angle. 7 I Therefore, the resultant of the vertical motion due-to iston unbalance which itself principally at the front of the en e, since the actuating force is forward 0 .the

body by 4 of t tion of the movements at the different points may be determined empirically or otherwise by observatiomor computation of the char-' center of mass of the motor unit, combines with the rocking action due to piston inertia torque, this latter motion mamfestin itself in the rear motor legs as an up an down movement. The two legs, moving in opposite direction, give a different motion atthe three points of suspension, but all of thesame frequency, which is twice the rate of rotation of the crankshaft. I,

. Furthermore we have found that the actual amplitude of these up and down vibratory movements is .relatively small and isindependent of'engine seed. Of course more energy is exerted at igher engine speeds so that the frame and attached parts are forced to vibrate with the engine, and these vibratlons become especially annoying and undesirable when their rate comes into resonance with any particular part of the car, such as the influence of the vibrations, the supporting means moves upwardly with it to an extent substantially equal to the natural amplitude of the vibrational movement, and similarly, when the engine tends to move downwardly, the supporting means goes with it, thus varying the dimensions of the supportmg means between the base and the vibratin an amount equivalent to the amphtude o the vibrations without varying the force exerted uponthe base through thepoints of support. 7

The direction and extent of variation in the 'tion of the supporting means at each points of support and the phase relaacteristics of the vibrations produced at each shown by way of illustration one formof adaptation of the invention to the mounting of an internal combustion engine upon the chassis of an automobile,-

1 v I Fig. 1 is a side elevation, with parts broken away, showing a. four-cylinder engine mounted upon chassis frame members Fig.- 2 is an end elevation, partly-1n section,online22of Fig.1; f v Fig. 3 is a front end elevation artly in sec- 7 tion, of the structure shown in ig. 1;v

Fig. 4- is a plan view, partly in'section, of the engine mounting on the left side of Fig.2; V 1 ig. 5,is.an enlarged detail ,view of the lever-actuating means also shown in Fig. 2;

Fig. 5. v 26 Referring to the drawings, 10 indicates an internal combustion engine having cylinders 11, 12, 13, 14, crank case includingupper and lower parts 15, 16, and fly wheel housing 17. These parts together with the pistons eratin through connecting rods upon cranks aft 18 may be of any usual or suitable construction. The usual cam shaftf19 is illustrated to be actuated in the customary manner at half crankshaft speed. The engine base in this instance comprises J a'pair of longitudinal side frame-or chassis members, 20, 21, and transverse framemembers 22, 23, shown as positioned respectively at the 'front and rear of the engine crank casing, member 23 b'ein located between the crankcasing and the y wheel housing. a The engine is shown as being provided with three ints of support corresponding to the well own -three oint sus nsion. One of these points, in icated as is adjacent to the front end of theengine, and the other two, indicated as B and, C respectively, are adjacent to the'rear of the engine and upon op- Iposite sides thereof. The supporting means at the point A is i1- lustrated in Fig. 3, the front cover of the crank case being removed to show parts which may be located within the casing. At this point the engine is supported upon a member 25 illustrated as a post secured at its base to the cross member 22 andextending at its upper end intothe interior of the crank case.

The upper end .of the post is provided with abearing for reception of the ivot or ful- 60 crum 26 ofa lever 27. The s orter end of the lever is formed at 28 to seat'in a bearing 29 which may be a part of the crank case. The longer end of the lever rests against a cam 30 formed upon the cam shaft 19. As the cam shaft rotates,therefore,theleveriscaused :Fig. 6 is a plan view of the detailsfshown determined that the upward and downward .movements thus permitted areequivalent to and synchronous with the vibrations tobe 7 neutralized. The engine as a whole is there.- .fore permitted to vibrate without varying the force exerted by it, due toits mass, upon the 1 supporting post, and as a result, the effect of thebvibrations is not transmitted tethe frame or. ase.

.A somewhat similar structure may be utilized at the points B and At the point B the cross member 23 carries a bracket 31 having arms 32, 33, apertured tov receive a pivot pin 34. The fly wheel housing 17 caries a bracket 35, having arms 36, 37, aperv a tured to receive the pin38. The lever 39 is journaled upon pin 38 and fulcrumed at its 1 shorter end upon pin 34." The longer armfl of the lever extends to a point in proximity to the rear end ofthe cam shaft 19 which is here formed with a cam 40. A plunger 41 mounted in abearing block 42 positioned in a herein the crank case 15, is arranged to engage cam 40 and theend of lever 39 and cause reclprocation of the leverby the action of the cam. ,In this case the vibrating body supported by bracket 35 upon pin 38 is perchronous with the normal vibrations. of the bod ,will ermit the vibrations totake place' .wit outbemg transmitted to-the base.

At the point C a bracket 45 carried by the 0 fly wheel housing supports a pin 46.. A bracket 47 carried by the'member '23 supportsa pivot pin'48. A lever 49 is journaled upon 'pin 46 and fulcrumed-at its shorter end-- upon pin 48. The longer arm of the lever ex- 1 tends to a oint near the end of lever 39 and is arrange to restupona lunger 5O reciprocably mounted in the bloc '42 and actuated by-cam 40. The arran ement of parts and the operationat point 6 are similar to those at point B and will be readily understood from the description alreadyg ven. In the structure as shown, since the vcam shaft is at one sided the engine, the lever 49 is shorter than the lever 39. The pivots 46 and 48 ing the levers and plungers this angular dis- 'tted to oscillate about the point of support 1 'at 34. These oscillations, being made synplacement may be made as great or as small as may be necessary without requiring the use of separate cams for the two levers, although the latter may be employed if desired.

The vibrations due to piston action in the four cylinder engine are of a frequency twice that of the crank shaft rotations, therefore, if a cam or other actuating device placed upon the crankshaft were used to effect the variations in position of the points of support such cam would have to produce two oscillations or actuations for each rotation. Since the cam shaft rotates at half crankshaft speed it is necessary that the cam or actuator; lo-

cated upon the cam shaft be arranged to produce'four actuations per rotation. The cams shown therefore each have four cam projections.

' The'cam shaft has been selected for illustration herein as the means for actuating the oscillatory supporting devices. It will be clear, however, that any other suitable moving part may be thus utilized. In the case of machines other than engines any shaft adapted to produce the desired frequency of impulses may be employed, or a separate actuating means may be provided.

The exact phase relationship of the movement of the vibrating body, as the en ine block, to the cycle of movements of the un al- 7 anced parts, as the reciprocating elements of the engine, may be most conveniently determined empirically. For this purpose the machine or engine'may be supported upon very long and flexible springs and set lnto o eration. The direction, amplitude and p ase relationship of the vibratory movements may then be readily observed. In the case of an engine of the type illustrated, viz., a four c lindervertical engine with the two interme iate cranks on the same side-of the crankshaft and at 180? from the two end cranks, the direction of the vibrations at the points of support will be approximately vertical. The center of gravlty of the reciprocating parts in this type of engine rises and lowers twice during each revolution of the cranks, being highest when the two pairs of pistons and corresponding cranks are, respectively, at top and bottom dead centers and lowest when the cranks are at 90 from this position. A mechanism suspended in such a way that it is free to move in. all directions tends to maintain its total center of gravity fixed in space. Therefore, if the center 'of gravity of a part of themechanism moves .in one direction the remainder of the mecha- ,nism tends to shift in the opposite direction.

Accordingly, in the present instance, the engine block tends to assume its highest position, in response-to the inertia forces-of the reciprocating parts, when the cranks are in a horizontal position and its lowest position when the cranks are at top and bottom dead centers, the intermediate positions following substantially a sine curve. The amplitude of movement may also be derived from the comutation of" the disturbing force, by wellknown text-book methods, and a comparison vof respective masses of the reciprocating and tions, comprising the combinationof a base means for supporting the body from the base and means for moving said supporting means in synchronism with the said vibrations and V in a direction and to such extent as to permit the body'to vibrate without transmission of the energy of such vibrations through the supporting means to the base.

2. The combination with a body having moving rts causing vibration and a base by which t e'body is supported of connecting means between said body and base and means actuated independently of the vibrations to positively ad ust the connecting means to compensate fpr the vibratory movement and permit the vibration without transmitting the energy thereof to the base.

3. The combination with an engine subject to vibration .at the point of support, and a base therefor of supporting means between said engine and base and means actuated by a moving part of the engine to adjust said supporting means in synchronism with the sai vibrations insuch manner as to permit the en 'ne to move in accordance with said vibratlons without transmitting the energy thereof to the base.

4w Structure in accordance with claim 3.

including a lever whereby the engine is supported and means for causing oscillations of said lever.

5. The combination of an engine subject to vibration, a frame, a lever pivotally connected to said frame and to said engine, said lever constituting a positioning element whereby the engine is positioned relatively to the ame, and means for causing oscillations of said lever in a direction and with an amplitude to rmit said vibrations without transmitting t e energy thereof to the frame.

6.- Structure as set forth in claim 3, the

last-nientiQned means including a cam ac-' tuated by the engine.

7. The combination with mechanism having moving parts tending to cause vibration of said-mechanisrm-of a base, means connecting said mechanism to said base including an oscillatingpart adapted to vary the distance between the mechanism and the .baseand base.

means for actuating saidoscillating partin synchronismfwith-said vibrations to permit v the mechanism to'vibrate without transmitting the energy of such vibrations the 8. Structure as set forth inclaim 7, said.

last-mentioned means being actuated by a;

moving part of the said mechanism. 9. A mounting for bodies subject tovibra z1' tions' comprising, in'combination with the body,a base,'means for positioning the body 1 relatively to the base, and means'for reducing the transmission of the energy of saidvibrations to. the base comprising mechanism for continuously .movin said positioning means in syn-chronism' w th: thesaid viibratio1.s,-and in direction -and to extent topermit.

thebodyflto vibrate without opposing substantial resistance to the vibrations.

a 10. A mounting for bodies subject to vibrationsfcomprising, in combination with the body, a base, means for positioning the body relatively to the, base, and means for continuously moving the positioning means to maintain the body in predetermined relationto the base, said. relationbeing varied in synchronism with said vibrations and in direction and. to extent to'permitthe movement oi the body relatively to the base in accordance with the said vibrations.

we 11. .A body including moving parts operative to set up vibrations of said body, a base engine to said frame including a non-re- -,s1l1ent part, and means acting upon said con necting means to move the said non-resilient.

- part to permit the position of the engine to vary relatively to the frame in synchronism fwith vibrations in said engine.

' 13. The structure as set forth the means for moving the non-resilient part being actuated by a moving part ofthe enine.

v being actuatedbythe engine cam shafit.

15. The combination of a machine subject Lto vibrations of substantially fixed amplitude v and direction, a support, means connecting -the machine and the support, and means for i said connectingmeans in positively movin ii said'vibrations so a to synchronism wit 1 cause the point of support to follow the machine in its vibratorymovement to prevent .55 transmission of vibrations'to thesupportl in claim 12,.

16. A mounting for machinessubject to vibrations due toinherent unbalance comprising the combination with such machine of a supporting base therefor and means for movin the machine relatively to the base at the polnts of support in the approximate direction and with approximately the same phase relationand amplitude with which the mabalance toreduce thereby the transmission of the energy of such vibrations to the base.

17. The combination with an'engine and supporting chassis, such engine belng subject to vibrations due to inherent unbalance of moving parts, of means for moving the engine relatively to the chassis'at a point of connection of the engine to, the chassis in the chine tends to move due to its inherent un-. v

approximate direction and with approximately the same phase relation and amplitude with .which the engine tends to move due to' such inherent unbalance to reduce thereby the transmission of the energy of such vibrations to the chassis. Y

In testimony whereof we atfix'our signatures."

' CALEB E. SUMMERS. I ROGER K. LEE.

14. The structure as set forth in claim 12, the means for moving the non-resilient part 

